Advanced Materials Research Vols. 403-408

Abstract: The pivotal role of lithium batteries in energy storage is a well known fact. But in today’s fast paced revolutionary world, problems like charge retaining difficulty, excess heat generation, leakage etc make them impossible devices for energy storage. Instead of going in for the conventional lithium batteries, a new battery can be brought into existence which uses the body fluid (blood) as its electrolyte. Inside the mystic human system, during the oxidation process of the carbohydrates we consume, electrons are liberated which may be used to power up a tiny battery inside, the rate of which is controlled by the nanobots. As multifunctionality is the need of the hour, numerous tiny sensors placed inside our body which operate on MEMS technique not only monitors the body tissues but also detects any block in arteries and veins, cancer causing cells and gives suitable command to the nanobots. The rate at which the nanobots clear the imperfection can be made faster by swarm intelligence. The multifunctionality aspect of nanobots is further enhanced as they act as an effective substitute for dialyser and pacemaker.

Abstract: This paper describes a simple algorithm for tracking path for a line following robot (black line on white background) with the information related to steering decision obtained from the images of the path by processing the images using MATLAB Image Processing Toolbox. The images are captured using MATLAB Image Acquisition Toolbox by triggering frames from a video in real time and applying the algorithm on these frames. This approach provides an improvement to the infrared sensor based robots, which tend to give random values due to unavailability of adequate light, are not independent of the shape of the path as there is no information of the path ahead, and shape and width of the path is also a deciding factor for sensor separation. This approach is inspired from the human vision of determining the deviation of the path by having knowledge of the path ahead by comparing the orientation of the path. This is a simple computational technique working on the pixel information of the image in comparison to other complex mathematical techniques available. The algorithm has been verified using a recorded video and correct deviation of the path has been observed.

Abstract: Photovoltaic inverters are important solar energy application. This paper presents a novel Fuzzy Adaptive Hysteresis Current Controller to control the inverter, used in the non-linear time-variant solar photovoltaic cell. The proposed controller has the advantages of both fuzzy as well as adaptive controller. It is capable of reducing the total harmonic distortion and to provide acceptable switching frequency. The mathematical model of Photovoltaic array is developed using the Newton’s method using the parameter obtained from a commercial photovoltaic data sheet under variable weather conditions, in which the effect of irradiance and temperature are considered. The modeled Photovoltaic array is interfaced with DC-DC boost converter, AC-DC inverter and load. A DC-DC boost converter is used to step up the input DC voltage of the Photovoltaic array while the DC-AC single-phase inverter converts the input DC comes from boost converter into AC. The performance of the proposed controller of inverter is evaluated through MATLAB-Simulation. Unlike standard adaptive controller designs, this adaptive fuzzy controller does not require an explicit mathematical model of the system. The results obtained with the proposed algorithm are compared with those obtained when using conventional fixed hysteresis current controller for single-phase photovoltaic inverter in terms of THD and switching frequency.

Abstract: The stabilization, tracking and pointing systems are essential features of modern fire control and surveillance systems. The criteria for precision stabilization may vary from a few hundred micro-radians to few nano-radians for achieving jitter free image depending upon the application scenario. The Line of sight (LOS) is stabilized by mounting the optical payload on a gimbal platform and designing the control system around them. The paper describes a choquet fuzzy integral based control algorithm developed for LOS controlling and stabilizing application. In this approach, q-measure is estimated to simplify the computation of λ-measure that aggregates the information from the weighted inputs. The output of fuzzy rules, which are formulated by defining the product of weighted inputs are required to compute the fuzzy measure in the form of Choquet fuzzy integral.

Abstract: Electric Power Distribution System is a complex network of electrical power system. Also, large number of lines on a distribution system experiences regular faults which lead to high value of current. Speedy and precise fault location plays a pivotal role in accelerating system restoration which is a need of modern day. Unlike transmission system which involves a simple connection, distribution system has a very complicated structure thereby making it a herculean task to design the network for computational analysis. In this paper, the authors have simulated IEEE 13- node distribution system using PSCAD which is an unbalanced system and current samples are generated at the substation end. Considering the application of signal processing tools to power systems a talk of modern day research, Gabor decomposition of the current samples are also presented which is utilised for locating all ten types of faults. It is kept in mind that Gabor transform has not been applied to current samples of distribution system as per the literature available till date.

Abstract: Three degrees of freedom (DOF) parallel manipulator is used in the applications such as base for various machining operations, drilling inclined holes, airplane and automobile simulators, walking machines, pointing devices, contour milling and machining etc. The 3 DOF parallel manipulator consists of a fixed platform and a movable platform, which are connected by means of three identical links. Pin joints are used to connect the one end of the link and the lead screw pair. This 3 DOF 1R2T parallel manipulator is having one orientation freedom and two translational freedom, which is actuated by means of screw pair, which in turn operated by a stepper motor. The inverse kinematics and velocity equations of this mechanism have been derived mathematically. Based on this inverse kinematics and velocity equations singularity analysis is completed. Two kinds of singularities are compared with ADAMS simulation results and a prototype of the manipulator is developed for further study.

Abstract: Recently, flexible joint lightweight robots are widely used in a variety of mobile robots or mechanical platforms, playing a more and more important role in the areas of space exploration, military reconnaissance, counter-terrorism, defusing, as well as home service. From the viewpoint of lightweight robot applications, there exist many different tasks under changing working conditions, either working in dangerous and unknown complex environment or closely contacting with human beings. Therefore, for a safe operation and high reliability, lightweight robots need not only high-precision position control but also compliance control, such that no injury on the robot and operated object will occur when interacting with the unknown environments. In order to make the manipulator contacts the environment compliantly, and reduces the instantaneous impact when collision occurs. This paper presented an interaction impedance control strategy for manipulator based on joint torque sensor, and combined with the trajectory regeneration with force feedback. Experiment was performed on a 5-DOF flexible joint lightweight manipulator. The experiment results of tapping on an egg showed the manipulator contacts the object compliantly and reduces collision impact, so the proposed approach was effectiveness and validity.

Abstract: his paper presents a robust stable controller for speed control of a linear permanent magnet DC motor. A fractional controller is presented and the optimal parameters of this controller are obtained using Particle Swarm Optimization (PSO) technique. Interval uncertainty is considered in the parameters of the DC motor. Stability of the closed loop system with the proposed controller in presence of interval uncertainty is verified through the extension of Kharitanov’s theorem for fractional order systems. Simulation results demonstrate the successful performance of the proposed controller.

Abstract: Intelligent Universal Transformer (IUT) will comprise in Advanced Distribution Automation (ADA) with a new invention in control and management in future. It evolves with a high speed traditional transformer in addition to power electronic base construction will eventuate to oil elimination, dimensional size and weight reduction. Adaptive Fuzzy Logic Control (AFLC) is an adaptive progressed method with the high system performance capability being raised even on the uncertainty conditions. It enhances system stability, improves flexibility and releases designers from precise mathematical model utilization. Expert designer Knowledge is a critical requirement for conventional fuzzy logic controller (FLC), in contrast the AFLC rules and parameters are generated by adaptive model and human knowledge will downright initialize the first parameters values. In this approach four layers IUT topology is considered for developing the end user service options as 48V DC, reliable power as 240V AC 400HZ and three phase power option. AFLC schemes are proposed for employing current and voltage controllers in input output stages. Real time voltage regulation, automatic sag correction, Harmonic Filtering, energy storage option and dynamic system monitoring are the resulting benefits of using IUT four layers topology. AFLC methodology, leading the system robustness in any cases of grid and load disturbances.

Abstract: Multi-level voltage source inverters offer several advantages such as a better output voltage with reduced total harmonic distortion (THD), reduction of voltage ratings of the power semiconductor switching devices and also the reduced electro-magnetic interference problems etc. This paper presents the application of Fast space vector pulse width modulation (SVPWM) method for multi-level diode clamped inverter feeding a three-phase Induction motor. The algorithm is independent of the number of inverter levels. In this the three vectors nearest to the reference vector are identified and their corresponding duty cycles are found. These values remain same regardless of number of inverter levels and the location of reference vector.